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JOSIAH SHANKLIN, OF PARKERSBURG, VIRGINIA.

SQUARE, SCALE, LEVEL, AND BEVEL.

Specification of Letters Patent No. 11,844, dated Qctober 24, 1854.1 j

To all whom t may concern Be it known that I, JosIAH SHANKLIN, of Parkersburg, in t-he county of Wood and the State of Virginia, have invented a new and Improved Instrument for the Use of Mechanics and others, called the Mechanics Companion'g and I do hereby declare that the following is a full and eXact description thereof, reference being had to the accompanying drawings, with their letters and figures, for the purpose of showing its construction and operation.

Figure 1 represents a piece of brass in the form of a square with its outer edges graduated in inches, from l to 5 or more, beginning the graduation at the corner or right angle and extending it each way. At or near the middle of each blade Z Z Z (Fig. 7) of this square is a groove about a. quarter of an inch wide cut parallel with its outer edges and extending `nearly to the end of each blade. On the other side of this square, there are degrees marked upon one or both of the blades, as will be more fully explained hereafter, This piece, and in fact the entire instrument may be made either of wood or metal. Fig. 2 represents a piece of brass, wood or metal about 7 inches long and sufficiently thick to give it strength, its upper edge divided oil' into inches and parts of inches, with a groove on each side of its center corresponding with the same in Fig. l. The left hand groove may be shorter than the right hand one, or if desired of the same length as shown by the dotted lines at A. On the under edge of this piece there is lefta tongue about an inch long and inch wide. Fig. 6 is a piece of the same metal or wood corresponding in every respect to Fig. 2, with this difference: It is not graduated into inches and it has a flange on the upper edge, which serves the purpose of a rest when applied to a piece of timber. The grooves in this piece must be of equal length, so that it would balance evenly if suspended from the point C. Fig. 3 is a thumb screw, and Fig. 4 the nut belonging to it. Of these there are two of each kind. Fig. 5 represent-s the instrument when all its parts are properly put together. To do this, take Fig. 2 and Fig. 6 and fasten them together with a pivot passing through the points B and C, with a washer between them, of convenient size, and of the thickness of the piece Fig. l. Let the ange on Fig; 6 project outward or downward. Fig. 6 is of course the under piece, and both Fig. 2 and Fig. 6 are fastened together by the pivot in such manner that they may turn upon the pivot freely. Having put these two pieces together, take the square (Fig. l) and slip each arm between the two pieces Figs. 2 and 6. Adjust the pieces so that the thumb screw may pass through the grooves, first on the left hand as at letter D Fig. 5, then placing the nut on the under side screw them fast. Adjust the right hand end, and screw them together in the salne manner, as shown at letter E, and the instrument is ready for use.

When used for a bevel- Tighten one of the screws so that the square may turn upon it as upon a pivot-and loosen the other screw, and any mechanic will at once see its convenience as a bevel.

T o get the length of rafters, braces, stair cases, dic-The base of a triangle is 4 feet, the upright 3 feet, what is the hypotenuse? Take the companion, loosen both screws, and slip the left end of the square until the 4th inch on it exactly coincides with the first inch on the cross piece, (Fig. 2), then screw the left hand moderately tight. Now raise the right end of the square until Fig. 3, or the 3d inch just clips the edge of the cross piece (see the pencil marks at let-ter F,) and it will strike the cross piece at five inches; hence the hypotenuse is 5 inches. Now tighten both screws and if for a brace or rafter, scribe the brace by the companion as now adjusted, in this manner. Letthe iange rest against one side of the timber, at the lett hand end, and scribe from G to H, across the timber, then measure 5 feet toward the right, lplace the companion as before and scribe from F to H, and you have .the length and shape of the brace or rafter. In the same manner may any side of a right angle triangle be found, thus saving the labor of calculation by square root. The inches may of course be regarded as feet, rods, miles, or parts thereof suiting the nat-ure of th-e calculation. This example is deemed sufficient to show the principle embraced, and the thousand uses to which it may be app-lied.

l'VLen used for a level-Take out both thumb screws and let the under cross piece Wit-h the flange upon it hang loosely, then, as seen by Fig. 7, screw the square and upper cross piece together in the same manner as before. When thus adjusted the under cross piece serves as a level, and thel degrees are marked on the under side of the square. If found more convenient the corners of the upper or front crosspiece (Fig. 2) may be clipped 0E as indicated by the dotted line J (Fig. 7 Its convenience inV this respect for masons, carpenters, &c. are too apparent to need further explanation.

Grlrio.l LOOM'Is, M. P. AMIss. 

